Protective clothing and containers of many types is well known for many and varied uses including protection from fire, vapors and harmful substances. Such clothing is often seen in suits for industrial workers, firemen, hazardous waste workers, race car drivers, airplane pilots and military personnel. Garments include not only complete hermetic suits, but also individual components such as trousers, jackets, gloves, boots, hats, head coverings, masks, etc.
Regulations restricting exposure to hazardous environments of various kinds, such as those contained in the Occupational Safety and Health Act, make it increasingly necessary to have better and more effective kinds of protective clothing. In particular, certain requirements by the U.S. Coast Guard and related requirements by other U.S. government agencies involve a total protective hermetic suit or envelope around the individual person to protect the worker from the widest possible range of hazardous materials.
Encapsulating suits are necessary for "immediately dangerous to life and health" (IDLH) environments. These suits must be air tight and worn with a self-contained breathing apparatus. The suit must be nonabsorbent, totally impermeable, and resistant to the widest range of chemicals and reagents. It should also be as fire resistant as possible. Since these suits are being worn by active individuals, they should also be flexible, abrasion resistant, lightweight, and should maintain their impermeability while being used. Such suits are commonly called "HAZ MAT" suits with class A level being the most vapor proof.
The garments presently available are almost invariably of thick construction and heavy in weight, and are often fabricated at least in part from materials impermeable to water or water vapor, such as natural and synthetic rubbers and elastomers, chlorinated rubbers, etc.
Protective clothing comprised of laminates of films have the problem of forming kinks when bent. This restricts motion and makes movement cumbersome. Moreover, much of the protective clothing is porous and provides little protection against hazardous chemical vapors.
It is therefore desirable to utilize an impermeable fabric which possesses heat sealing properties and is resistant to a large range of chemicals. Sewn seams are permeable to chemical vapors, whereas heat fused seams are impermeable. Even seams put together with adhesive (hot melt or pressure sensitive) can pull apart or be undercut by vapors.
The optimum sealing of seams, which join the various pieces of laminated fabric to form a protective suit against chemical vapors have a seam that is equal to or better than the laminate fabric against permeable chemical vapors. Therefore, it is preferred to have a laminated fabric which heat seals to itself so that a tape related to the barrier films can be used to heat seal the seam and give excellent chemical protection.
U.S. Pat. No. 4,515,761 to Plotzker describes a protective garment for use in detoxification which contains a layer of a highly fluorinated ion exchange polymer having sulfonic acid multivalent metal ion salt functional groups.